Oliver Wuesten MD, Presenter: Nothing to Disclose

Val Murray Runge MD, Abstract Co-Author: Research grant, Bayer AG

Miguel Trelles De Belaunde MD, Abstract Co-Author: Nothing to Disclose

Claudia Cotes MD, Abstract Co-Author: Nothing to Disclose

Matthew Miller, Abstract Co-Author: Nothing to Disclose

Egemen Tuzun MD, Abstract Co-Author: Nothing to Disclose

Mark W. Lenox PhD, Abstract Co-Author: Nothing to Disclose

Theresa W. Fossum DVM, Abstract Co-Author: Nothing to Disclose

John Nicholas Morelli MD, Abstract Co-Author: Nothing to Disclose

Gabriele A. Krombach MD, PhD, Abstract Co-Author: Nothing to Disclose

To evaluate the difference in image quality using time-resolved contrast-enhanced magnetic resonance angiography (CE-MRA) at 3 T between the two macrocyclic gadolinium based contrast agents gadobutrol and gadoterate meglumine in a porcine model for intracranial aneurysms.

In this IACUC approved study, bilateral carotid aneurysms were created surgically in 8 domestic swine using an isolated segment of the external jugular vein. Time resolved CE-MRA studies were performed at 3 T using a TWIST sequence optimized for high temporal resolution (0.5 s). Voxel size was 1.4 x 1.1 x 3.0 mm3. Three identical CE-MRA sequences were acquired, each with the same amount of administered gadolinium ion, comparing 1 ml gadobutrol (1.0 M) at an injection rate of 2 ml/s to 2 ml gadoterate meglumine (0.5 M) at 2 ml/s and 4 ml/s. Image quality was assessed quantitatively by measurement of the contrast-to-noise ratio (CNR) and qualitatively using a blinded read. DSA correlation was performed in all cases.

All 16 aneurysms were successfully imaged with CE-MRA and DSA. The blinded read showed a preference of gadobutrol over gadoterate meglumine for assessment of the aneurysm and the feeding vessel with high inter-observer agreement (κ = 0.72 for the aneurysms and κ = 0.81 for the feeding vessels). Both readers ranked gadobutrol enhanced MRA as the best in 87.5% and 93.8% of cases for assessing the aneurysm and in 93.8% and 87.5% for assessing the feeding vessel, respectively. Multifactor crossover design analysis showed significantly higher CNR in the aneurysms for gadobutrol (CNR=133±44) when compared to gadoterate meglumine at 2 (CNR=94±35) and 4 ml/s (CNR=102±38). In the feeding vessel CNR was significantly higher for gadobutrol (CNR=68±20) when compared to gadoterate meglumine at 4 ml/s (49±17).

Low-dose dynamic CE-MRA is feasible for the evaluation of intracranial aneurysms with high temporal resolution. CNR levels and reader preference are higher for gadobutrol compared to gadoterate meglumine, reflecting the greater relaxivity and 1 molar formulation. Higher injection rates of gadoterate meglumine did not improve image quality.

CE-MRA of small berry aneurysms at 3 T is superior with gadobutrol compared to gadoterate meglumine, important in the context of low dose protocols to reduce the risk of nephrogenic systemic fibrosis.

Wuesten, O, Runge, V, Trelles De Belaunde, M, Cotes, C, Miller, M, Tuzun, E, Lenox, M, Fossum, T, Morelli, J, Krombach, G, Comparison of Two Different Macrocyclic Gadolinium Chelates Using Low-Dose, Time-resolved 3D Magnetic Resonance Angiography at 3 T in a Porcine Model of Carotid Aneurysm.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11003710.html